In the last decade or so, a significant amount of attention has been focused on sleeping and in particular how are sleep comfort effects a person's ability to get a good nights sleep. Experts have recognized that there is no common preferred sleep position or sleeping surface that will be equally comfortable to all people in terms of how well they sleep. Rather, different people require different sleep surfaces and sleep positions to get a good nights rest. One person may sleep best on his/her stomach on a soft mattress, while another person may sleep best on his/her side on a medium firm surface, and yet another person may sleep best on his/her back on a very firm surface. Furthermore, the same person may vary his/her sleep habits on a periodic basis. For example a person may sleep on his/her back one night, his/her stomach the next night, and his/her side another night. In each sleep position, different firmness sleep surfaces may be required by even the same person to maximize his/her comfort.
Thankfully, mattress companies have recognized the differences in how different people sleep and have brought mattresses to the market in which the sleeper can adjust the firmness of the mattress on an as-needed basis. For example, one company sells a mattress in which the users can adjust the pressure level of air contained in air bladders in the mattress to adjust the mattress's firmness. Other companies offer beds that can be independently tilted at various locations resulting in a myriad of configurations. Never in history has the consumer's ability to change the characteristics of his/her sleep surface been so great.
Unfortunately, pillow technology has not kept pace with mattress technology, and accordingly, there are very few if any pillows for sale in the marketplace that are user easily user customizable and adjustable. Pillows, however, just like mattresses can greater effect how well a person sleeps. Some people prefer thick soft pillows. Others prefer relatively thin pillows. Others, who regularly switch between different sleeping positions, may desire to have pillows of differing thicknesses and levels of firmness readily available to accommodate two or more different sleeping positions.
To make matters worse, hotels rarely offer the guest more than a single pillow choice. Depending on the patron of a hotel, the supplied pillows may be too thick, to thin, or not supportive enough. Probably as often as hotel patrons cannot sleep because of the type of mattress provided, other patrons fail to get a good nights sleep well because the provided pillows are uncomfortable to them.
The typical standard pillow has been around for a long time and is still in use by a majority of people in the United States. Referring to FIG. 1, a typical rectangular pillow 10 comprises top and bottom sheets 15 & 20 of fabric that are sewn together along its edges 25. The resulting enclosure is filled a stuffing 30 materials such as, but not limited to, polyester fiberfill, feathers, cotton batting and foam particulate. The type and amount of filling material determines the pillow's firmness and loft.
As shown in FIG. 2, a traditional pillow 10 is thickest at its center 30 thinning towards each of it four edges 25. Because of this thinning toward its edges, the traditional pillow typically does not provide full support to the nape 45 of a person's neck 35 when a person 40 is sleeping on his/her back as illustrated in FIG. 3. Rather, it leaves a gap 45 between the top of the pillow and the nape of the neck that increases the strain on the neck. It is appreciated excessive neck strain can cause a person to wakeup with a stiff neck.
Additionally, in higher loft traditional pillows 10 that are filled with a fibrous polymeric material such as polyester, compression of the center of the pillow causes both the filler to be pushed towards the edges of the pillow and the fibers in the filler that extend from the portion of the pillow compressed by a person's head and the portion behind the head to become tensioned. The tension developed in these fibers causes a force 50 to be exerted on the rear 55 of the head generally forcing it upwardly and rotating the person's chin 60 generally counterclockwise. This can also cause neck discomfort and cause a person to wakeup with a stiff neck 35.
Various types of pillows have been produced that minimize or eliminate the problems associated with traditional pillows. For instance, U.S. Pat. No. 5,271,114 teaches a generally traditional pillow that is divided into two portions with one portion being of a different length than the other portion. A pillow case is provided that includes strategically positioned snap so that the pillow can be partially folded over on to itself at the intersection of the two portions and secured, thereby creating a thicker section to support a person's neck. While this pillow is an improvement for a back sleeper who needs better neck support, it is not an ideal pillow configuration for a side or stomach sleeper that does not require neck support. Further, such a pillow would not serve a person that switches their sleeping positions during the night.
Another type of pillow that has become popular is the contoured foam pillow, which is often comprised of a unitary block of viscoelastic foam material such as the pillow described in U.S. Pat. No. 5,797,154 of Contreres and the pillow described in U.S. Pat. No. 5,802,644 of Scheurer. These types of pillows define a trough that receives the back of a person's head. A thicker section is provided to support the person's neck. Further, because of the nature of viscoelastic foam material, the pillow tends to support the head more evenly than a traditional pillow. However, there are several drawbacks to contoured viscoelastic foam pillows.
First, contoured viscoelastic pillows are designed primarily for back sleepers and are typically not suitable for stomach, side or position-switching sleepers. Next, viscoelastic foam is well known for absorbing and retaining heat. As a sleep period progresses, a viscoelastic foam pillow will absorb heat from a person's head potentially making the pillow uncomfortably warm.
Also, the typical contoured viscoelastic foam pillow comprises two ridges proximate either edge of the pillow where the foam is relatively thick and the trough or area of lower thickness therebetween. In use, a user places his/her head in valley with one of the ridges situated underneath the neck for support thereof. The ridges are typically of different thicknesses, so the user is able to choose the one ridge that best suits his/her preferences. Unfortunately, the ridge that is not being used to support the neck is situated behind the back of the head and the unused ridge cause a force 50 to be exerted on the rear 55 of the head generally forcing it upwardly and rotating the person's chin 60 generally towards his/her chest.
Finally, like the other types of pillows described above, contoured foam pillows are not user adjustable or customizable. For instance, while the pillow of Scheurer can be compressed and rolled up for travel purposes, a special compression “Tapper with hook and loop fasteners is required to hold the pillow in this alternative configuration. Certainly, however, the rolled-up configuration with the foam highly compressed and a wrapper covering the pillow would be unsuitable for use to sleep or to comfortably lie upon.